This part is a kind of semiconductor called AP9985GM-HF.

Function of this product has N-CHANNEL ENHANCEMENT MODE POWER MOSFET.

Manufacturers : Advanced Power Electronics

Image and pinout :

Some of the text within the PDF file :

Advanced Power Electronics Corp. AP9985GM-HF Halogen-Free Product N-CHANNEL ENHANCEMENT MODE POWER MOSFET ▼ Low On-Resistance ▼ Simple Drive Requirement ▼ Fast Switching Characteristic ▼ RoHS Compliant & Halogen-Free D D D D SO-8 SG S S Description AP9985 series are from Advanced Power innovated design and silicon process technology to achieve the lowest possible onresistance and fast switching performance. It provides the designer with an extreme efficient device for use in a wide range of power applications. The SO-8 package is widely preferred for all commercial-industrial surface mount applications using infrared reflow technique and suited for voltage conversion or switch applications. BVDSS RDS(ON) ID 40V 15mΩ 10A D G S Absolute Maximum Ratings@Tj=25o.C(unless other [ ... ]

AP9985GM-HF PDF Datasheet Download